I'm going to put a flatbed stake on my '46 2 ton, so i'm in a very simular situation as yourself.
My preferred plan of attack would be to find an old truck with the flatbed/stakebed steel frame in good condition, then just bolt it on the truck and replace the wood.
Stake/flat beds really aren't all that complex.. just a steel frame around the outside with the pockets cut in it, with left to right cross pieces (made of wood or steel) to support the 'deck' wood. The whole assembly gets bolted to the frame, usually with a steel or wood 'spacer' to help give adaquate clearence of the deck from the rear wheels.
My problem is, i'm not much of a welder.. so the 'already made' bed frame is what i'll be looking for.
I've seen some guys make an ALL WOOD flatbed.. for stake pockets, they just put metal brackets on the sides to hold the 2x4 stakes.. I don't know if i'd be confident enough in the durability of that design for normal, everyday use.. I like the idea of the steel frame and under frame support, with a wood deck.
